New heroes emerge in battle against COVID-19

FOR THE LOVE OF THE ANIMALS

By Beth Leermakers

Drugs. Bombs. Truffles. Bed bugs. Malaria. With their powerful sense of smell, dogs can be trained to detect all these things. And now we can add the novel Coronavirus (COVID-19) to that list. Several organizations worldwide are training dogs to sniff out the COVID-19 virus. 

If dogs can successfully detect COVID-19, they could be used at airports to quickly identify travelers infected with the virus. 

Scent detection dogs could also be used in other public areas such as nursing homes or businesses to spot people who may be asymptomatic and unaware that they are carrying the contagious virus. The scent detection would likely be used as pre-screening to indicate individuals who need further testing. 

A UK-based charity called Medical Detection Dogs (MDD) is partnering with researchers at the London School of Hygiene and Tropical Medicine (LSHTM) and Durham University to train dogs to detect COVID-19. “We know that other respiratory diseases like COVID-19 change our body odor, so there is a very high chance that dogs will be able to detect it,” says Professor James Logan, head of the Department of Disease Control at the LSHTM.

Changes in our health often alter the way we smell. Human bodies constantly emit a cocktail of chemicals known as volatile organic compounds (VOCs) in sweat, saliva, urine and breath that change when cells grow (due to cancer) or when they die after being infected — such as by a virus. Dogs, with 50 times more smell receptors than people, are well adapted to smell these VOCs, and they have a proven track record at detecting diseases and changes in blood sugar due to diabetes. 

MDD has successfully trained dogs to detect malaria, prostate and colon cancer, Parkinson’s and bacterial infections. They’ve extensively researched dogs’ sense of smell and believe they can train dogs to detect the VOCs associated with COVID-19. Dogs can detect subtle changes in the temperature of the skin, so they may also be able to sense when a person is running fever. 

Closer to home, University of Pennsylvania researchers are studying whether nine dogs can detect a distinct smell in people infected with COVID-19. Researchers start by repeatedly allowing dogs to sniff containers of COVID-19 positive urine samples and giving them treats. 

Then they present a sample that is not positive, without the treats. The dogs learn that there is something unique about the COVID-19 sample. Then the researchers test whether dogs can recognize the odor when a person (who has many other odors) is holding the sample. 

The researchers are optimistic dogs will be able to identify COVID-19, based on MDD’s research with malaria detection, which confirmed dogs can pick up odors in asymptomatic patients.  

Dogs are already being used to detect COVID-19 in the Dubai airport. 

The Dubai dogs, who began sniffing swabs of passengers’ armpit sweat in mid-August, have about 94.5 percent accuracy, according to Dominique Grandjean, a professor at the National Veterinary School of Alfort in France and head of an international research team, who began training 16 experienced police and firefighter dogs to detect COVID-19 in France in March. 

Thanks to their super sniffers, scent detection dogs are joining the other life-saving heroes in our fight against this insidious pandemic.